The unrelenting Texas drought has produced a cruelly ironic twist: cattle dying from too much water.

Agriculture officials in parched Texas say there are no hard numbers on how many head of cattle have died but reports of deaths from too much water or too little are on the rise across the nation's leading cattle production state.

"They over drink because they're thirsty," says Robert Sprowls of the Texas Veterinary Medical Diagnostic Laboratory in Amarillo. "Once they fill up on water it happens pretty quickly."

Producers are losing cattle after moving them from withered pastures where water tanks have dried up. Once in new pastures, cattle that die take in too much water too quickly. The animals die within minutes and their carcasses are found near the stock tanks from which they were drinking, Ted McCollum, a beef cattle specialist with Texas AgriLife Extension Service in Amarillo, says.

Texas is coming off its driest nine-month period ever and its hottest June on record. More than 90% of the state is in the two most severe drought stages. The cattle deaths are occurring earlier, in part because of lack of forage growth in pastures.

"We are seeing more incidents of heat stress in cattle," he says. "More incidents of death and problems with health."